Kerberos is a network authentication system which is available for Unix, Windows, Macintosh, and I'm sure lots of other platforms.
How does this relate to [[OpenAFS]]? [[OpenAFS]] uses Kerberos to perform strong authentication for clients connecting to the AFS filespace. If you're new to Kerberos, you should take a look at the Kerberos FAQ located at . For the impatient, a quick list of useful Kerberos-related terms will be available at [[KerberosTerms]].
Note that there are two versions of Kerberos in wide usage. The latest is [[KerberosV]], but AFS, for historical reasons, uses a modified version of Kerberos 4 (see [[KaServer]]). However, AFS can be integrated into a [[KerberosV]] realm, and in fact is highly suggested for any new installations of AFS. See [[SettingUpAuthentication]].
Installing [[KerberosV]] along with [[OpenAFS]] will provide the basis for many other very cool features, such as a single repository for all authentication information for an administrative domain, integration with the Windows 2000/XP login mechanism, and even single-sign-on capability. Note that the further down you get in that list, the harder things become. :)
The installation documentation on the [[OpenAFS]] web site unfortunately does not include any information on integrating AFS into a [[KerberosV]] realm. (Work on install document & gotchas page later)
To compile [[OpenAFS]] with [[KerberosV]] support you need to use the --with-krb5-conf=/path/to/krb5-config flag to configure.
If you're using [[KerberosVMIT]] versions 1.2.6 or later, you'll need to add a section to krb5.conf on the krb524d host if you wish to continue using old-style [[KerberosIV]] ticket derived tokens.
[appdefaults]
afs_krb5 = {
REALM.NAME = {
afs = false
afs/cell.name = false
}
}
Where REALM.NAME and cell.name are the names of your [[KerberosRealm]] and [[AFSCell]] respectively.
If you already have a working AFS cell using [[KaServer]], check out Derrick Brashear's document for converting from the [[KaServer]] to [[HeimdalKTH]] [here](http://lost-contact.mit.edu/afs/net/project/afs32/andrew.cmu.edu/usr/shadow/ka2heim.txt):
For now a few links... explanations to follow later:
- Setting up [[OpenSSH]] to use [[KerberosV]] authentication: you can either use PAM to authenticate people (boring) or you can add the patches at to use existing [[KerberosV]] tickets for single-sign-on and automatic ticket forwarding (interesting). Note that by default this patch won't grab tickets when logging in via password - post small patch to enable this later.
- If you're having trouble with Ken Hornstein's AFS-Kerberos5 migration kit available at , see for tips. In particular check out the Makefile patches.
- [[DenizKanca]] posted [Kerberos 5 and OpenAFS - Notes available](https://lists.openafs.org/pipermail/openafs-info/2003-January/007799.html) on 19-Jan-2003 saying
> ... I took some notes on what I did when I set up Kerberos 5 and
>
> [[OpenAFS]]
>
> . Please note that this was done on a Redhat 8.0 installation and Redhat specifics (rpm, directory names etc) are assumed throughout.
>
> [http://www.arayan.com/da/yazi/OpenAFS\_Kerberos\_5.html](http://www.arayan.com/da/yazi/OpenAFS_Kerberos_5.html)
>
> ...
- John Boyland has a [patch](http://www.cs.uwm.edu/~boyland/afs-krb5.patch) for Ken Hornstein's AFS Migration Kit v 2.0 that fixes some typos and includes updates suggested by other [[OpenAFS]] contributors.
- An older AFS link page:
Some other issues to explain:
- PAM modules available for K5
- Admin differences between various K5 implementations
- krb524d -- which uses a K5 TGT to produce a V4 AFS service ticket which the [[CacheManager]] needs. It does not need to run on the same machine as the [[KerberosV]] server but just needs access to the AFS principal's key. This is not needed for [[HeimdalKTH]] which implements V4 and V5 services, but is for MIT and [[ActiveDirectory]].
- encryption types -- this is a per key property and V5 supports several (while V4 only supported one, namely what V5 calls des-cbc-crc). However, this is not the V5 default (which I think is des3) so you need to ensure that the AFS principal uses des-cbc-crc.
- [[StringToKey]] differences
### Links
#### [[KerberosV]] version 1.3.1
[Main Site](http://web.mit.edu/kerberos/)
- [install guide](http://web.mit.edu/kerberos/www/krb5-1.3/krb5-1.3.1/doc/krb5-install.html)
- [user guide](http://web.mit.edu/kerberos/www/krb5-1.3/krb5-1.3.1/doc/krb5-user.html)
- [admin guide](http://web.mit.edu/kerberos/www/krb5-1.3/krb5-1.3.1/doc/krb5-admin.html)
- [krb425 guide](http://web.mit.edu/kerberos/www/krb5-1.3/krb5-1.3.1/doc/krb425.html)
-- Ted Anderson - 22 Jan 2002 -- Derrick Brashear - 23 Jan 2002 -- Ted Anderson - 23 Jan 2002 -- Jason Garman - 30 Jan 2002 -- Ted Anderson - 31 Jan 2002
----
See [[HeimdalKTH]], [[ActiveDirectory]], [[KerberosDCE]], [[AuthCommands]], [[SettingUpAuthentication]].